docs-v2/content/influxdb3/cloud-serverless/query-data/sql/explore-schema.md

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Markdown

---
title: Explore your schema with SQL
description: >
When working with InfluxDB's implementation of SQL, a **bucket** is equivalent
to a database, a **measurement** is structured as a table, and **time**,
**fields**, and **tags** are structured as columns.
menu:
influxdb3_cloud_serverless:
name: Explore your schema
parent: Query with SQL
identifier: query-sql-schema
weight: 201
influxdb3/cloud-serverless/tags: [query, sql]
list_code_example: |
##### List measurements
```sql
SHOW TABLES
```
##### List columns in a measurement
```sql
SHOW COLUMNS IN measurement
```
---
{{% sql/sql-schema-intro %}}
## List measurements in a bucket
Use `SHOW TABLES` to list measurements in your InfluxDB bucket.
```sql
SHOW TABLES
```
{{< expand-wrapper >}}
{{% expand "View example output" %}}
Tables listed with the `table_schema` of `iox` are measurements.
Tables with `system` or `information_schema` table schemas are system tables that
store internal metadata.
| table_catalog | table_schema | table_name | table_type |
| :------------ | :----------------- | :---------- | ---------: |
| public | iox | home | BASE TABLE |
| public | iox | noaa | BASE TABLE |
| public | system | queries | BASE TABLE |
| public | information_schema | tables | VIEW |
| public | information_schema | views | VIEW |
| public | information_schema | columns | VIEW |
| public | information_schema | df_settings | VIEW |
{{% /expand %}}
{{< /expand-wrapper >}}
## List columns in a measurement
Use the `SHOW COLUMNS` statement to view what columns are in a measurement.
Use the `IN` clause to specify the measurement.
```sql
SHOW COLUMNS IN home
```
{{< expand-wrapper >}}
{{% expand "View example output" %}}
| table_catalog | table_schema | table_name | column_name | data_type | is_nullable |
| :------------ | :----------- | :--------- | :---------- | :-------------------------- | ----------: |
| public | iox | home | co | Int64 | YES |
| public | iox | home | hum | Float64 | YES |
| public | iox | home | room | Dictionary(Int32, Utf8) | YES |
| public | iox | home | temp | Float64 | YES |
| public | iox | home | time | Timestamp(Nanosecond, None) | NO |
{{% /expand %}}
{{< /expand-wrapper >}}